Subject: Re: [v3] net: ethernet: cavium: octeon: octeon_mgmt: Handle return
 NULL error from devm_ioremap
To: Arvind Yadav <arvind.yadav.cs@gmail.com>, <peter.chen@nxp.com>,
        <fw@strlen.de>, <david.daney@cavium.com>, <f.fainelli@gmail.com>
References: <1481742210-5609-1-git-send-email-arvind.yadav.cs@gmail.com>
CC: <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>
From: David Daney <ddaney@caviumnetworks.com>
Message-ID: <41599714-309c-8590-b2b0-e468cffb57b5@caviumnetworks.com>
Date: Wed, 14 Dec 2016 11:28:03 -0800
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On 12/14/2016 11:03 AM, Arvind Yadav wrote:
> Here, If devm_ioremap will fail. It will return NULL.
> Kernel can run into a NULL-pointer dereference.
> This error check will avoid NULL pointer dereference.

I have asked you twice already this question, but could not determine 
from your response what the answer is:

Q: Have you tested the patch on OCTEON based hardware that contains the 
"octeon_mgmt" Ethernet ports?  Please answer either "yes" or "no".


Thanks,
David Daney


>
> Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
> ---
>  drivers/net/ethernet/cavium/octeon/octeon_mgmt.c | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c b/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
> index 4ab404f..33c2fec 100644
> --- a/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
> +++ b/drivers/net/ethernet/cavium/octeon/octeon_mgmt.c
> @@ -1479,6 +1479,12 @@ static int octeon_mgmt_probe(struct platform_device *pdev)
>  	p->agl = (u64)devm_ioremap(&pdev->dev, p->agl_phys, p->agl_size);
>  	p->agl_prt_ctl = (u64)devm_ioremap(&pdev->dev, p->agl_prt_ctl_phys,
>  					   p->agl_prt_ctl_size);
> +	if (!p->mix || !p->agl || !p->agl_prt_ctl) {
> +		dev_err(&pdev->dev, "failed to map I/O memory\n");
> +		result = -ENOMEM;
> +		goto err;
> +	}
> +
>  	spin_lock_init(&p->lock);
>
>  	skb_queue_head_init(&p->tx_list);
>